“Today, an estimated one in three Americans are obese.”
A worker operates a press at the New Orleans Times-Picayune, typical of the physical activity that was common in many workplaces in earlier decades.
Looking beyond poor eating habits and a couch-potato lifestyle, a group of researchers has found a new culprit in the obesity epidemic: the American workplace.
A sweeping review of shifts in the labor force since 1960 suggests that a sizable portion of the national weight gain can be explained by declining physical activity during the workday. Jobs requiring moderate physical activity, which accounted for 50 percent of the labor market in 1960, have plummeted to just 20 percent.
The remaining 80 percent of jobs, the researchers report, are sedentary or require only light activity. The shift translates to an average decline of about 120 to 140 calories a day in physical activity, closely matching the nation’s steady weight gain over the past five decades, according to the report, published Wednesday in the journal PLoS One.
Today, an estimated one in three Americans are obese. Researchers caution that workplace physical activity most likely accounts for only one piece of the obesity puzzle, and that diet, lifestyle and genetics all play an important role.
Body Mass Index (BMI) is a number calculated from a person’s weight and height. BMI provides an indicator of body fatness for most people and is used to screen for weight categories that may lead to health problems.
Women tend to believe they look their best at values between 20 to 22 and men are usually satisfied with a BMI of 23 to 25. If your BMI is between 17 to 22, your life expectancy is longer than average. You don’t need to lose weight. If your BMI is between 23 and 25, you are not considered overweight by most people. But if your BMI is 26 or more, that’s not good.
What is the waist circumference?
Waist circumference is the distance around your natural waist (just above the navel). If your BMI is greater than or equal to 25 kg/m2, your goal for waist circumference is less than 40 inches if you’re a man and less than 35 inches if you’re a woman.
What is the body mass index (BMI)?
Body mass index assesses your body weight relative to height. It’s a useful, indirect measure of body composition because it correlates highly with body fat in most people. Weight in kilograms is divided by height in meters squared (kg/m2). In studies by the National Center for Health Statistics,
BMI values less than 18.5 are considered underweight.
BMI values from 18.5 to 24.9 are healthy.
Overweight is defined as a body mass index of 25.0 to less than 30.0. A BMI of about 25 kg/m2 corresponds to about 10 percent over ideal body weight. People with BMIs in this range have an increased risk of heart and blood vessel disease.
Obesity is defined as a BMI of 30.0 or greater (based on NIH guidelines) — about 30 pounds or more overweight. People with BMIs of 30 or more are at higher risk of cardiovascular disease.
Extreme obesity is defined as a BMI of 40 or greater.
Some well-trained people with dense muscle mass may have a high BMI score but very little body fat. For them, the waist circumference, the skinfold thickness or more direct methods of measuring body fat may be more useful measures.
How do you find your BMI risk level?
Use a weight scale on a hard, flat, uncarpeted surface. Wear very little clothing and no shoes.
Weigh yourself to the nearest pound.
With your eyes facing forward and your heels together, stand very straight against a wall. Your buttocks, shoulders and the back of your head should be touching the wall.
Mark your height at the highest point of your head. Then measure your height in feet and inches to the nearest 1/4 inch. Also figure your height in inches only.
Find your height in feet and inches in the first column of the Body Mass Index Risk Levels table. The ranges of weight that correspond to minimal risk, moderate risk (overweight) and high risk (obese) are shown in the three columns for each height.
(BMI under 25)
(BMI 30 and above)
118 lbs. or less
143 lbs. or more
123 or less
148 or more
127 or less
153 or more
131 or less
158 or more
135 or less
164 or more
140 or less
169 or more
144 or less
174 or more
149 or less
180 or more
154 or less
186 or more
158 or less
191 or more
163 or less
197 or more
168 or less
203 or more
173 or less
209 or more
178 or less
215 or more
183 or less
221 or more
188 or less
227 or more
193 or less
233 or more
199 or less
240 or more
204 or less
246 or more
To calculate your exact BMI value, multiply your weight in pounds by 703, divide by your height in inches, then divide again by your height in inches. (Adapted from Obesity Education Initiative: Clinical Guidelines on the Identification, Evaluation, and Treatment of Overweight and Obesity in Adults, National Institutes of Health, National Heart, Lung, and Blood Institute, Obesity Research 1998, 6 Suppl 2:51S-209S)
To Your Health: Getting the facts on your child’s BMI
Published: Tuesday, September 14, 2010
By Annie Linton, M.Ed
Congress has officially proclaimed September 2010 as the first-ever Childhood Obesity Awareness Month.
We are all becoming painfully aware that pediatric and adolescent obesity is epidemic to our nation. According to the CDC (Center for Disease Control and Prevention), more than one third of U.S. adults — more than 72 million people — and 16 percent of U.S. children are obese.
Since 1980, obesity rates for adults have doubled and rates for children have tripled. The consequences of obesity make our children at risk for adult-like disease such as hypertension (high blood pressure), Type 2 diabetes, orthopedic and joint problems, cardiovascular disease and cirrhosis of the liver, as well as psychological ailments associated with severe weight gain.
With this being said, the Pennsylvania Department of Health’s (DOH) annual school health screening procedures now include calculating body mass index (BMI) to help track students’ growth patterns and identify potential weight-related health problems.
For those not familiar with the term, BMI is basically a measurement using height and weight. BMI = weight (kg) / height (m)Ç BMI does not measure body fat directly, but research has shown that BMI correlates to direct measures of body fat. It is screening tool and not a diagnostic tool (Barlow and Dietz, 1998).
With kids and teens, body fat changes with age and the amount of body fat differs between girls and boys. So BMI calculations are different for kids than adults. When your child’s BMI is calculated, the BMI number is plotted on a specific growth chart (for either girls or boys) to obtain a percentile ranking which will categorize the child as underweight, healthy, overweight or obese. (www.cdc.gov/)
So the question is, what do we do with this BMI report card that the school nurse sends home? If your child is categorized as overweight or obese, making the right decision will not be easy. But to determine if excess fat is a problem, a health care provider may need to perform further assessments.
These assessments might include skin fold thickness measurements, evaluations of diet, physical activity, family history, and other appropriate health screens. Many parents may use this as a starting block for family fitness, better food choices and overall healthy lifestyle, which is always good practice whether your child has a weight problem or not.
Others may choose nothing as they may not really know what to do for their overweight child. Join a gym? See a doctor? Get a personal trainer? Most insurances do not cover weight management services in their medical plans despite the medical implications that obesity may cause.
Dr. Sandy Hassink, director of pediatric weight management clinic at AI DuPont Hospital for Children in Wilmington, suggests that if you are worried about your child’s weight, contact your pediatrician. Get a sense of what your child’s weight trends have been (is it a steady weight gain or sudden), what are they eating and what are their eating habits, and what kind of activity they do on a regular basis. (Pediatric Obesity, American Academy of Pediatrics 2007)
Lastly, weight management is a team effort. Singling out your child to lose weight without the support of the family will not be effective. Make a commitment for the entire family to make some positive, healthy changes such as healthier snacks and meals, less TV and more family activity. Dr. Hassink also suggests, “the changes that will help your child manage his/her weight today could also keep a serious illness from developing later.” And that is good food for thought.
Contributor Annie Linton, M.Ed, CPT, is a Pediatric Clinical Exercise Physiologist at Children’s Hospital of Philadelphia, personal trainer and adjunct professor in exercise science. She resides in Springfield.